Electric machine with Q-offset grooved interior-magnet rotor and vehicle

• US 10,547,222 B2
• Filed: 12/07/2018
• Issued: 01/28/2020
• Est. Priority Date: 10/16/2008
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Saito, Yasuyuki, Goto, Tsuyoshi, Nakayama, Kenichi, Hino, Noriaki, Sugimoto, Shinji
• Primary Examiner(s): Le, Dang D
• Application Number:
  US16/213,462
• Publication Number:
  US 20190115796A1
• Time in Patent Office: 417 Days
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/025 using field orientation; Vector control; Direct Torque Control [DTC]
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/429 Current
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2270/142 acoustic
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: H02K 1/24 Rotor cores with salient poles ; Variable reluctance rotors
• CPC Class Codes: H02K 1/276 : Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
• CPC Class Codes: H02K 1/2766 : having a flux concentration effect
• CPC Class Codes: H02K 2201/06 : Magnetic cores, or permanent magnets characterised by their skew
• CPC Class Codes: H02K 2213/03 : Machines characterised by numerical values, ranges, mathematical expressions or similar information
• CPC Class Codes: H02K 29/03 : with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
• CPC Class Codes: H02K 7/006 : Structural association of a motor or generator with the drive train of a motor vehicle
• CPC Class Codes: H02P 27/06 : using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

A rotating electric machine includes a stator having a stator coil and a rotor provided rotatably around a specific rotation axis with respect to the stator. The rotor includes a plurality of magnets, a plurality of magnetically-assisted salient pole members provided between poles of any adjacent two magnets from among the plurality of magnets, and a magnetoresistance variation unit provided in the magnetically-assisted salient pole member along an axial direction of the rotation axis at a position offset in a circumferential direction of the rotation axis from a q-axis passing through a salient pole center of the magnetically-assisted salient pole member. The amount of offset of the magnetoresistance variation unit from the q-axis varies depending on positions of the magnetically-assisted salient pole members so that torque fluctuations cancel each other when power is applied.

Claims

1. A rotor for a rotating electrical machine, comprising:

a plurality of magnets; and

a plurality of magnetically-assisted salient pole members provided at a core portion between the magnets, wherein

the rotor includes insert holes for the magnets;

edges of the magnets and the insert holes form magnetic air gaps at regions overlapped with the magnetically-assisted salient pole members;

the magnetic air gaps include first magnetic air gaps and second magnetic air gaps, each of the second magnetic air gaps being opposite to the first magnetic air gaps across a q-axis passing through a salient pole center of each of the magnetically-assisted salient pole members and being formed smaller than the first magnetic air gaps at the regions overlapped with the magnetically-assisted salient pole members; and

the magnets provided with the first magnetic air gaps at both ends along a circumferential direction and the magnets provided with the second magnetic air gaps at both ends along a circumferential direction are alternately arranged in the rotor.

2. A rotating electrical machine comprising:

the rotor according to claim 1; and

a stator having a stator coil, wherein

the stator coil is wound by distributed winding.

3. An electric vehicle comprising:

a rotating electrical machine according to claim 2;

a battery that supplies direct current power; and

a conversion unit that converts the direct current power of the battery into an alternating current power and supplies the alternating current power to the rotating electric machine, wherein

a torque of the rotating electric machine is utilized as a driving force.

4. A rotor for a rotating electrical machine, comprising:

a plurality of magnets; and

a plurality of magnetically-assisted salient pole members provided at a core portion between the magnets, wherein

the rotor includes insert holes for the magnets;

edges of the magnets and the insert holes form magnetic air gaps at regions overlapped with the magnetically-assisted salient pole members;

the magnetic air gaps include first magnetic air gaps and second magnetic air gaps, each of the second magnetic air gaps being opposite to the first magnetic air gaps across the magnet and being formed smaller than the first magnetic air gaps at the region overlapped with the magnetically-assisted salient pole member; and

the magnetically-assisted salient pole members provided with the first magnetic air gaps and the magnetically-assisted salient pole members provided with the second magnetic air gaps are alternately arranged in the rotor.

5. A rotating electrical machine comprising:

the rotor according to claim 4; and

a stator having a stator coil, wherein

the stator coil is wound by distributed winding.

6. An electric vehicle comprising:

a rotating electrical machine according to claim 5;

a battery that supplies direct current power; and

a conversion unit that converts the direct current power of the battery into an alternating current power and supplies the alternating current power to the rotating electric machine, wherein

a torque of the rotating electric machine is utilized as a driving force.